The oral treponeme bacterium Treponema sp. OMZ 838 was originally isolated from a human necrotizing ulcerative gingivitis (NUG) lesion. Its taxonomic status remains uncertain. The complete genome sequence length was determined to be 2,708,067 bp, with a G+C content of 44.58%, and 2,236 predicted coding DNA sequences (CDS).
Plasma homocysteine (Hcy) is a modifiable, independent risk factor for cardiovascular disease (CVD) and is affected by both environmental and genetic factors. This study aimed to describe the gender- and age-specific distribution of Hcy concentration for 1117 subjects aged 10–66 years, a subset of a community-based rural Chinese twin cohort. In addition, we examined environmental and genetic contributions to variances in Hcy concentration by gender and age groups. We found that the distribution pattern for Hcy varied by both age and gender. Males had higher Hcy than females across all ages. Elevated Hcy was found in 43% of male adults and 13% of female adults. Moreover, nearly one fifth of children had elevated Hcy. Genetic factors could explain 52%, 36% and 69% of the variation in Hcy concentration among children, male adults and female adults, respectively. The MTHFR C677T variant was significantly associated with Hcy concentrations. Smokers with the TT genotype had the highest Hcy levels. Overall, our results indicate that elevated Hcy is prevalent in the children and adults in this rural Chinese population. The early identification of elevated Hcy will offer a window of opportunity for the primary prevention of CVD and metabolic syndrome.
homocysteine; Chinese twins; heritability; gender difference; smoking
Myocardial infarction (MI) is a serious complication of Coronary Artery Disease (CAD). Previous studies have identified genetic variants on chromosome 9p21 and 6p24 that are associated with CAD, but further studies need to be conducted to investigate whether these genetic variants are associated with the pathogenesis of MI. We therefore performed this study to assess the association between the risk of MI and SNP rs10757274 on chromosome 9p21 and SNP rs6903956 on chromosome 6p24, and to explore the gene-environment interactions in a Chinese population.
A hospital-based case–control study, consisting of 502 MI patients and 308 controls, was conducted in a Chinese population. Demographic, behavioral information and clinical characteristics were collected, and genotyping of the two SNPs was performed using single base primer extension genotyping technology. The unconditional logistic regression (ULR) method was adopted to assess the association of the two SNPs with MI risk. Both generalized multifactor dimensionality reduction (GMDR) and ULR methods were applied to explore the effect of gene-environment interactions on the risk of MI.
After adjusting for covariates, it was observed that SNP rs10757274 on chromosome 9p21 was significantly associated with MI. Compared with subjects carrying the AA genotype, subjects carrying the GA or GG genotypes had a higher MI risk (ORa = 1.52, 95% CI:1.06–2.19, pa = 0.0227; ORa = 2.40, 95% CI:1.51–3.81, pa = 0.0002, respectively). Furthermore, a two-factor gene-environment interaction model of CDKN2A/B (rs10757274) and type 2 diabetes mellitus (T2DM) was identified to be the best model by GMDR (p = 0.0107), with a maximum prediction accuracy of 59.18%, and a maximum Cross-validation Consistency of 10/10. By using the ULR method, additive interaction analysis found that the combined effect resulted in T2DM-positive subjects with genotype GG/GA having an MI risk 4.38 times that of T2DM-negative subjects with genotype AA (ORadd = 4.38, 95% CI:2.56–7.47, padd < 0.0001).
These results show that gene polymorphism of CDKN2A/B (rs10757274) is associated with MI risk in a Chinese population. Furthermore, T2DM is likely to have an interaction with CDKN2A/B (rs10757274) that contributes to the risk of MI.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2261-14-170) contains supplementary material, which is available to authorized users.
The oral spirochete bacterium Treponema putidum inhabits human periodontal niches. The complete genome sequence of the OMZ 758T (ATCC 700334T) strain of this species was determined, revealing a 2,796,913-bp chromosome, with a G+C content of 37.30% and a single plasmid (pTPu1; 3,649 bp) identical to pTS1 from Treponema denticola.
This study is aimed to investigate the clinical significance and the short-term prognostic value of fragmented QRS (fQRS) for patients with acute myocardial infarction (AMI). Three hundred patients with AMI were tested with retrospective analysis on the patients’ clinical information, hospitalized treatment, fQRS onset time, location of lesions, and other relevant data, in order to assess the relationship between the presence of fQRS and its prognosis. The rates of malignant cardiac arrhythmia, left ventricular systolic dysfunction (LVSD), and mortality in the positive fQRS group were 13.6%, 29.2%, and 23.7%, respectively, with all showing a p value <0.05. For the ST segment elevation myocardial infarction (STEMI) subgroup, all the rates showed significant differences with a p value <0.01, while for the non-STEMI (NSTEMI) subgroup showed no significant differences. In patients with a positive fQRS, there were no differences in malignant cardiac arrhythmia between patients with and without percutaneous coronary intervention (PCI) (p>0.05). As for the LVSD and mortality, the p values between patients with and without PCI were 0.031 and 0.000, respectively, suggesting statistical significance. The results imply that AMI patients with positive fQRS especially for the patients with STEMI had higher rates of malignant cardiac arrhythmia, LVSD, and mortality than the non-fQRS group. Patients of AMI with positive fQRS, who underwent early revascularization, could lower the incidence of the cardiovascular event. In addition, the presence of fQRS could be used as an indication of early intervention treatment for patients.
Fragmented QRS; Acute myocardial infarction; Short-term prognosis
Objective: High body mass index (BMI) is considered as the most important risk factor for elevated serum alanine aminotransferase (ALT) concentration. This study examined an array of factors, including waist circumference (WC) and folate deficiency, which may mediate the association of BMI with serum ALT concentration in Chinese hypertensive adults without known hepatic diseases. Methods: A multicenter, cross-sectional study was carried out. A total of 378 patients with mild or moderate hypertension and without known hepatic diseases were recruited from five hospitals in Harbin, Shanghai, Beijing, Xi’an, and Nanjing. Results: Of the 360 hypertensive patients with complete data in our final analysis, 13.6% had high ALT concentrations (>40 IU/L). Factors including BMI, WC, triglyceride level, and folate concentration were associated with ALT concentration in univariate analysis. Consistently higher prevalence rates of elevated ALT were observed in subjects with lower folate concentrations (≥12 vs. <12 nmol/L, 9.9% vs. 17.8%, P=0.03), with higher BMI (≥28 vs. <28 kg/m2, 21.5% vs. 11.4%, P=0.02) or higher WC (≥90 vs. <90 cm, 18.5% vs. 10.0%, P=0.02). However, in multivariate analysis, the association between BMI and ALT concentration disappeared (P=0.802 in males and 0.369 in females), while WC in females (P<0.001) and folate concentration (P=0.036 in males and 0.044 in females) remained as significant predictors for ALT concentration. Conclusions: This multicenter study demonstrated that WC and low folate concentration were important factors underlying the association between BMI and ALT concentrations in Chinese hypertensive adults without known hepatic diseases.
Alanine aminotransferase (ALT); Body mass index (BMI); Waist circumference (WC); Folate
This study is the first systematic review of risk factors for stroke in China and supports the importance of current public health initiatives to manage the risk factors appropriately to reduce risk of stroke in high risk patients. Additionally, this study has been co-authored by prominent Chinese and US physicians and researchers with expertise in cardiovascular disease, neurologic disorders, epidemiology, and real world data. While there have been several systematic reviews of real world associations of risk factors for coronary artery disease, none focus specifically on the population of China, where there is growing evidence that such risk factors are poorly treated or uncontrolled, especially in rural areas.
To better understand the impact of traditional cardiovascular risk factors on risk of coronary artery disease (CAD) in China, a systematic review of all Chinese observational studies published in either English or Chinese in MEDLINE and EMBASE over the last 5 years was performed and the association between any of 5 traditional risk factors (ie, hypertension, diabetes, elevated lipid levels, obesity, and smoking) and the risk of CAD was studied.
Methods and results
The study found a consistent relationship between lipid levels and CAD. Higher low-density lipoprotein cholesterol values were associated with greater risk of CAD, with an odds ratio as high as 3.31. Other factors found to be significant contributors to the risk of CAD included hypertension (crude odds ratio range of 1.40–5.11), diabetes (1.50–5.97), and smoking (1.37–5.19). An association between obesity and CAD in China was observed, but the evidence supporting this was considered weak due to the paucity of studies found as part of this review.
This review provides a systematic summary of CAD risk factors in China and demonstrates the important differences that exist in CAD risk factors between countries and regions. Approaches to reduce CAD globally must take into account the unique risk factors that drive CAD in each country and region as is demonstrated by these findings.
coronary disease; risk factors; smoking; diabetes; hypertension; dyslipidemia
The oral spirochete bacterium Treponema denticola is associated with both the incidence and severity of periodontal disease. Although the biological or phenotypic properties of a significant number of T. denticola isolates have been reported in the literature, their genetic diversity or phylogeny has never been systematically investigated. Here, we describe a multilocus sequence analysis (MLSA) of 20 of the most highly studied reference strains and clinical isolates of T. denticola; which were originally isolated from subgingival plaque samples taken from subjects from China, Japan, the Netherlands, Canada and the USA.
The sequences of the 16S ribosomal RNA gene, and 7 conserved protein-encoding genes (flaA, recA, pyrH, ppnK, dnaN, era and radC) were successfully determined for each strain. Sequence data was analyzed using a variety of bioinformatic and phylogenetic software tools. We found no evidence of positive selection or DNA recombination within the protein-encoding genes, where levels of intraspecific sequence polymorphism varied from 18.8% (flaA) to 8.9% (dnaN). Phylogenetic analysis of the concatenated protein-encoding gene sequence data (ca. 6,513 nucleotides for each strain) using Bayesian and maximum likelihood approaches indicated that the T. denticola strains were monophyletic, and formed 6 well-defined clades. All analyzed T. denticola strains appeared to have a genetic origin distinct from that of ‘Treponema vincentii’ or Treponema pallidum. No specific geographical relationships could be established; but several strains isolated from different continents appear to be closely related at the genetic level.
Our analyses indicate that previous biological and biophysical investigations have predominantly focused on a subset of T. denticola strains with a relatively narrow range of genetic diversity. Our methodology and results establish a genetic framework for the discrimination and phylogenetic analysis of T. denticola isolates, which will greatly assist future biological and epidemiological investigations involving this putative ‘periodontopathogen’.
Treponema denticola; Periodontal disease; Phylogeny; Multilocus sequence analysis; MLSA; Spirochete; Oral microbiota; Infectious diseases; Dentistry
The current standard of care for cervical myopathy is anterior discectomy and fusion (ACDF). Although well tolerated in the short term, this treatment might ultimately result in progressive degeneration of adjacent motion segments. Artificial disc arthroplasty offers the theoretical advantage of preservation of motion at the operative level with consequent stress reduction at adjacent levels.
We compared function, radiographic measures, and incidence of complications at 3-year followup after cervical disc arthroplasty with the Bryan® prosthesis and ACDF in patients with cervical myelopathy.
Patients and Methods
Eighty-three patients with cervical myelopathy were randomized to undergo arthroplasty with implantation of a Bryan® cervical disc prosthesis (n = 41) or ACDF (n = 42). Patients were assessed preoperatively to 3 years postoperatively using the modified Odom’s criteria, Japanese Orthopaedic Association scale, SF-36, and Neck Disability Index. ROM, stability, and subsidence of the prostheses were evaluated radiographically.
Patients who received the Bryan® prosthesis scored significantly better in three of the four functional assessment methods used (Japanese Orthopaedic Association scale, SF-36, and Neck Disability Index). ROM was retained by the patients in the Bryan® group but not in the patients in the ACDF group. Patients in the Bryan® group had fewer complications, primarily because dysphagia occurred in only one patient in the Bryan® group but in seven patients in the ACDF group. Other complications included pseudarthrosis in three patients in the ACDF group and one patient had spontaneous fusion, one had deep vein thrombosis, and one had heterotopic ossification in the Bryan® group.
Bryan® cervical disc arthroplasty appears reliable and effective in the treatment of cervical myelopathy.
Level of Evidence
Level II, therapeutic study. See the Guidelines for Authors for a complete description of the levels of evidence.
As a member of Glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors, Tirofiban had been shown to improve myocardial reperfusion and clinical outcomes in patients undergoing percutaneous coronary intervention (PCI), but the optimal timing of administration of Tirofiban remains unclear. In order to compare the effects of upstream versus downstream administration of Tirofiban in Chinese patients with mid to high risk, non-ST elevation acute coronary syndrome (ACS) referred for PCI, a multi-center, randomized, controlled, prospective study will be conducted. A total of 500 mid to high risk, non-ST-segment elevation myocardial infarction (NSTEMI) ACS patients will be recruited for this study. Patients will be randomized to Tirofiban upstream administration group (initiated 12 h before PCI) and Tirofiban downstream administration group (initiated at cath-lab after angiography). Thrombolysis in myocardial infarction (TIMI) flow grades, TIMI myocardial perfusion grades (TMPG), and Corrected TIMI frame counting (CTFC) before and after PCI, as well as clinical outcomes during the hospital stay, and within 30 days after PCI will be compared between the two groups. This study will provide evidence on the optimal timing for initiating administration of Tirofiban in mid to high NSTEMI ACS subjects undergoing PCI.
Acute coronary syndrome; Percutaneous coronary intervention; glycoprotein IIb/IIIa receptor; Tirofiban; Thrombolysis in myocardial infarction
To investigate the distributions of HLA-B alleles and estimate their associations with idiopathic male infertility in Chinese Han population.
Polymerase chain reaction-sequence-based typing (PCR-SBT) method was used for DNA typing at HLA-B locus in 109 patients with idiopathic male infertility and 152 healthy controls in male Han population of Shaanxi Province, situated in northwestern China.
In total, we detected 45 HLA-B alleles in idiopathic infertile patients, 48 HLA-B alleles in control subjects. However, no significant differences of these allelic frequencies were found between the infertile patients and the controls.
HLA-B gene was unlikely a major risk factor of idiopathic male infertility in this sample population. As different populations have different HLA polymorphisms, investigation of the relationship of other HLA genes and idiopathic male infertility with larger sample size, is warranted in the future.
Human leukocyte antigen (HLA)-B; Polymerase chain reaction-sequence-based typing (PCR-SBT); Idiopathic male infertility
Plasma level of total homocysteine (tHcy) is negatively correlated with kidney function in general population. However, the causal mechanism of this correlation is poorly understood. The purpose of this study is to investigate the association of methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism, which is a major genetic determinant of the plasma tHcy level, with estimated glomerular filtration rate (eGFR) in Chinese.
A total of 18 814 hypertensive patients (6 914 males, 11 900 females) were included in the study.
Association between the eGFR and MTHFR C677T genotype was examined by sex-specific regression analyses. In males, TT genotype was associated with 1.37 ml/min/1.73 m2 decrease in eGFR (p = 0.004) and with an increased risk (OR = 1.32, p = 0.008) for the lowest quintile of eGFR after adjusting for age, BMI, and blood pressures. However, such association was not observed in females (p > 0.05). This association suggests MTHFR C677T polymorphism may play a role in the regulation of eGFR in males.
MTHFR 677 T is a risk allele for decreased kidney function in Chinese males, implicating this gene in the pathogenesis of chronic kidney disease (CKD).
MTHFR C677T polymorphism; eGFR; CKD
This study examined the prevalence of impaired fasting glucose (IFG) and diabetes and their associated factors in 17,184 Chinese hypertensive adults aged 45–75 years.
A cross-sectional investigation was carried out in a rural area of Lianyungang, China. Previously undiagnosed diabetes [fasting plasma glucose (FPG) ≥7.0mmol/l] and IFG (6.1–6.9mmol/l) were defined based on FPG concentration. Previously diagnosed diabetes was determined on the basis of self-report. Total diabetes included both previously diagnosed diabetes and previously undiagnosed diabetes.
The prevalence of previously diagnosed diabetes, undiagnosed diabetes, and IFG were 3.4%, 9.8%, and 14.1%, respectively. About 74.2% of the participants with diabetes had not previously been diagnosed. In the multivariable logistic-regression model, older age, men, antihypertensive treatment, obesity (BMI ≥25kg/m2), abdominal obesity (waist circumference ≥90cm for men and ≥80cm for women), non-current smoking, a family history of diabetes, higher heart rate, lower physical activity levels, and inland residence (versus coastal) were significantly associated with both total diabetes and previously undiagnosed diabetes. Furthermore, methylene- tetrahydrofolate reductase (MTHFR) 677 TT genotype was an independent associated factor for total diabetes, and current alcohol drinking was an independent associated factor for previously undiagnosed diabetes. At the same time, older age, men, abdominal obesity, non-current smoking, current alcohol drinking, a family history of diabetes, higher heart rate, and inland residence (versus coastal) were important independent associated factors for IFG.
In conclusion, we found a high prevalence of diabetes in Chinese hypertensive adults. Furthermore, about three out of every four diabetic adults were undiagnosed. Our results suggest that population-level measures aimed at the prevention, identification (even if only based on the FPG evaluation), and treatment of diabetes should be urgently taken to overcome the diabetes epidemic in Chinese hypertensive adults.
Objective: To investigate the relationship between renal function and clinical outcomes among patients with acute ST-segment elevation myocardial infarction (ASTEMI), who were treated with emergency percutaneous coronary intervention (PCI). Methods: 420 patients hospitalized in Peking University First Hospital, diagnosed with ASTEMI treated with emergency (PCI) from January 2001 to June 2011 were enrolled in this study. Estimated glomerular filtration rate (eGFR) was used as a measure of renal function. We compared the clinical parameters and outcomes between ASTEMI patients combined renal insufficiency and the patients with normal renal function. Results: There was a significant increase in the concentrations of fibrinogen and D-Dimer (P<0.05) and a much higher morbidity of diabetes mellitus in the group of patients with chronic kidney disease (CKD; eGFR<60 ml/(min·1.73 m2)) (P<0.01). CKD (eGFR<60 ml/(min·1.73 m2)) was an independent predictor of in-hospital mortality for patients hospitalized with ASTEMI receiving PCI therapy rapidly (P=0.032, odds ratio (OR) 4.159, 95% confidence interval (CI) 1.127–15.346). Conclusions: Renal insufficiency is an independent predictor of in-hospital mortality for patients hospitalized with ASTEMI treated with primary PCI.
Acute myocardial infarction (AMI); Percutaneous coronary intervention (PCI); Renal function; Estimated glomerular filtration rate (eGFR); Mortality
Background and objective: In clinical practice, the standard of secondary prevention for coronary heart disease (CHD) is quite disappointing in China. The physicians’ shortage of knowledge of secondary prevention guidelines is thought to be a key factor contributing to the inadequate and delayed translation of guidelines into clinical practice. The purpose of this study is to investigate the influence of physicians’ characteristics, including their education and work experience, on their knowledge of secondary prevention in China. Methods: A representative questionnaire survey was made of physicians from cardiology departments in 35 tertiary hospitals in China. The survey contained 19 questions on knowledge of guideline recommendations for the secondary prevention of CHD. We collected basic information about the physicians, including their educational degree, clinical practice duration/work experience and geographic region. Results: In total, 864 physicians participated in the survey. Eight hundred and thirty-seven completed questionnaires were analyzed. For 6 of the 19 questions, physicians with a postgraduate degree were more likely to answer correctly than those without such a degree. For 11 of the 19 questions, physicians with more than three years’ clinical experience were more likely to answer correctly than those who had less than three years’ experience. For 5 of the 19 questions, physicians from eastern areas were more likely to answer correctly than those from mid/western areas. The mean total score of correct answers to the questionnaire was 11.69 points. Educational degree and clinical practice duration affected total scores significantly while practice location did not (β=0.500, P=0.004; β=0.979, P=0.000; and β=0.228, P=0.162, respectively). Even if a relatively low score of 12 is taken as a threshold level of acceptable knowledge (defined as a pass), the pass rate of all physicians was only 53.9%. Educational degree and clinical practice duration affected pass rate significantly while practice location did not (95% CI: 1.222–2.248, P=0.001; 95% CI: 1.773–3.140, P=0.000; and 95% CI: 0.993–1.758, P=0.056, respectively). Conclusions: Physicians with a clinical practice duration of more than three years knew more about secondary prevention guidelines than those with less experience. Physicians with a postgraduate degree knew more about secondary prevention guidelines than those without a postgraduate degree. However, overall knowledge of secondary prevention guidelines for CHD was poor among this group of physicians from tertiary hospitals.
Coronary heart disease; Secondary prevention; Guidelines; Survey
This study aimed to investigate if the homocysteine-lowering efficacy of two commonly used physiological doses (0.4 mg/d and 0.8 mg/d) of folic acid (FA) can be modified by individual methylenetetrahydrofolate reductase (MTHFR) C677T and/or methionine synthase (MTR) A2756G polymorphisms in hypertensive Chinese adults.
A total of 480 subjects with mild or moderate essential hypertension were randomly assigned to three treatment groups: 1) enalapril only (10 mg, control group); 2) enalapril-FA tablet [10:0.4 mg (10 mg enalapril combined with 0.4 mg of FA), low FA group]; and 3) enalapril-FA tablet (10:0.8 mg, high FA group), once daily for 8 weeks.
After 4 or 8 weeks of treatment, homocysteine concentrations were reduced across all genotypes and FA dosage groups, except in subjects with MTR 2756AG /GG genotype in the low FA group at week 4. However, compared to subjects with MTHFR 677CC genotype, homocysteine concentrations remained higher in subjects with CT or TT genotype in the low FA group (P < 0.05 for either of these genotypes) and TT genotype in the high FA group (P < 0.05). Furthermore, subjects with TT genotype showed a greater homocysteine-lowering response than did subjects with CC genotype in the high FA group (mean percent reduction of homocysteine at week 8: CC 10.8% vs. TT: 22.0%, P = 0.005), but not in the low FA group (CC 9.9% vs. TT 11.2%, P = 0.989).
This study demonstrated that MTHFR C677T polymorphism can not only affect homocysteine concentration at baseline and post-FA treatment, but also can modify therapeutic responses to various dosages of FA supplementation.
Folic acid supplementation; MTHFR C677T polymorphism; MTR A2756G polymorphism; Homocysteine-lowering efficacy
Reperfusion is the key strategy in acute ST-segment elevation myocardial infarction (STEMI) care, and it is time-dependent. Shortening the time from symptom to reperfusion and choosing the optimal reperfusion strategy for STEMI patients are great challenges in practice. We need to improve upon the problems of low reperfusion rate, non-standardized treatment, and economic burden in STEMI care. This article briefly reviews the current status of reperfusion strategy in STEMI care, and also introduces what we will do to bridge the gap between the guidelines and implementation in the clinical setting through the upcoming China STEMI early reperfusion program.
Acute ST-segment elevation myocardial infarction (STEMI); Reperfusion; Percutaneous coronary intervention (PCI); Fibrinolysis
Objective: To investigate the effect of enalapril on plasma homocysteine (Hcy) levels and the association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with the changes of Hcy levels in response to enalapril among patients with essential hypertension. Methods: A total of 130 patients with mild-to-moderate essential hypertension were enrolled and enalapril was orally administered at a dose of 10 mg/d for eight weeks. Plasma Hcy levels were measured by denaturing high-performance liquid chromatography (DHPLC) at baseline and after eight weeks of treatment. Genotyping of MTHFR C677T polymorphism was performed by TaqMan probe technique. Results: Compared with baseline, plasma Hcy levels did not change significantly after eight weeks (P=0.81). Stratified by baseline Hcy levels, a significant increase in plasma Hcy levels (P=0.02) among those with Hcy <10 μmol/L was observed, in contrast to no significant changes in plasma Hcy levels (P=0.54) among those with Hcy ≥10 μmol/L. No significant association was observed between MTHFR C677T polymorphism and changes in Hcy levels in response to enalapril. Conclusions: Enalapril may cause an increase in plasma Hcy levels among the hypertensives with low baseline Hcy levels. There was no significant association between MTHFR C677T genotypes and changes in Hcy levels in response to enalapril among subjects with essential hypertension.
Essential hypertension; Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism; Enalapril; Homocysteine
Deubiquitinating enzymes (DUBs) play an important role in ubiquitin-dependent processes as negative regulators of protein ubiquitination. Ubiquitin-specific protease 26 (USP26) is a member of this family. The expression of Usp26 in mammalian testis and in other tissues has yet to be fully elucidated. To study the expression of Usp26 mRNA and protein in various murine tissues, reverse transcription (RT)-PCR and immunohistochemistry analyses were carried out. The RT-PCR analysis showed that the Usp26 transcript was expressed in all of the tested tissues. USP26 protein localization was examined by immunohistochemistry, and it was shown that USP26 was not detectable at 20 days postpartum, with the expression restricted to the cytoplasm of condensing spermatids (steps 9–16), Leydig cells and nerve fibers in the brain. In addition, the USP26 protein was detected at moderate levels in myocardial cells, the corpus of epidydimis, epithelium of the renal tubules and the seminal gland of postnatal day 35 mice. Its spatial and temporal expression pattern suggests that Usp26 may play an important role in development or function of the testis and brain. Further research into these possibilities is in progress.
ubiquitin-specific protease 26 (USP26); Usp26 gene; deubiquitination enzymes; protein degradation,; spermatogenesis; mouse